多分支管路合流分流结构能有效降低管路密度，提升空间利用率，但不合理的结构设计容易造成过大的压力损失、过大的流量分配差异。文中提出了一种多分支管路合流分流最优化设计的数值方法，利用参数化分析法研究了雷诺数、出入口面积比、公共腔室末端封闭腔长度、分支管间距以及分支管数量等参数对流量分配、压力损失的影响规律。结果表明：合流腔存在压力恢复区，其对各支路的流量分配及压力损失存在影响；雷诺数对流量分配存在影响，增大雷诺数会增加压力损失、增大流量分配差异；公共腔室末端封闭腔长度对流量分配、压力损失的影响可忽略；出入口面积比、分支管间距、分支管数量与流量分配、压力损失存在重要关联，管路结构的优化设计中需综合考虑这些因素。文中结果可用于指导多分支管路合流分流结构的最优化设计。

Confluence and distribution of multi-branch pipeline （CDMBP） can effectively reduce pipeline density and improve space utilization，but unreasonable structural design can easily cause too much pressure loss and excessive flow distribution difference.A numerical method for the optimal design about CDMBP is proposed in this paper.The paper studies the influence law of multiple parameters，including Reynolds number，outlet and inlet area ratio，closed cavity length at the end of the common chamber，branch pipe spacing and the number of branch pipes，on the flow distribution and pressure loss with parametric analysis.The results show that：there is a pre-ssure recovery zone in the confluence and diversion cavity，which has an impact on the flow distribution and pre-ssure loss of each branch; the Reynolds number has an impact on the flow distribution; the increase of the Reynolds number may increase the pressure loss and the difference of flow distribution; the influence of flow distribution and pressure loss from the length of the end common chamber is negligible; the outlet and inlet area ratio，branch pipe spacing，and the number of branch pipes are importantly related to flow distribution and pressure loss.These factors need to be comprehensively considered in the optimization design of the pipeline structure.These results can be used to guide the optimal design of the CDMBP.